The campaign manager for Republican congressional candidate Carl DeMaio (CA) once offered a set of tips for identifying opposition research trackers looking to catch DeMaio in a gaffe or compromising moment: if the person in question is young or black they could very well be a tracker.

Specifically, the campaign manager, Tommy Knepper, said in an email exchange on April 19 obtained by The Washington Examiner, that possible trackers could be spotted if they’re young, African American, young and at a Saturday morning event, or very talkative to staffers.

The emails are the latest revelation in a campaign that has gotten national attention mostly for a former top staffer accusing DeMaio of sexual harassment and DeMaio’s staff, in response, accusing that staffer of breaking into a campaign office and also saying he was fired for a plagiarism scandal.

The email exchange reported by the Examiner on Friday started when DeMaio said he saw two trackers at an event. Knepper, in the email change, eventually offered his advice for picking out opposition trackers. Here’s what he said in the email:

1. Young-red flag

2. black-red flag

3. young at saturday morning event-HUGE red flag

4. Very curious and want to talk to staff a a lot-red flag

DeMaio, in response, according to the Examiner, said “Drop black from the criteria. Other 3 ok.”

The emails also show that DeMaio staffers laughing about a report from Buzzfeed that said Sen. Rand Paul (R-KY) plagiarized —an especially ironic fact given that the DeMaio campaign would eventually be caught in a plagiarism scandal.

“So embarrassing,” DeMaio spokesman Dave McCulloch wrote.

“Yep….It’s pretty bad when people are starting to plagiarize the plagiarizer,” said Todd Bosnich, the staffer who would eventually accuse DeMaio of sexual harassment.

The race for California’s 52nd Congressional District between DeMaio and Rep. Scott Peters (D-CA) has been a top House race this cycle.